The ABKey plugin for Apple's Address Book allows you to quickly view GPG key information for contacts as well as specify per-contact preferences for how GPGMail (the Apple Mail plugin for GPG) handles encrypting and signing of emails.

ACCELA is a library of wrapper classes for the Mac OS toolbox. It features a complete set of Carbon Events classes, which can also be used with PowerPlant. Other classes cover Navigation Services, Core Foundation, QuickTime, QuickDraw, AppleEvents, etc.

A collection of frameworks for use by Cocoa applications. Includes AGRegex, a Perl-compatible regular expression framework using the PCRE library, AGSocket, a networking framework supporting asynchronous I/O, and AGProcess, a framework for obtaining Unix

ALX3000 is the "NeXT generation newsreader" for Mac OS X. Build from scratch using Cocoa it is fast and works well with all system services. The core of the application was developed by the authors of the popular Alexandra newreader for NeXTSTEP.

APM(All Platform Messenger) Is a Web Messenger Useing php/MySQL storage for quick and easy Messaging once Pre-Alfa has been competed the steps in the OS'es will begin This system is its own not working with other systems

The AUGUI framework is a set of classes to be used to ease development of custom Carbon edit views for Mac OS X Audio Units. The classes are based on the HIFramework and on the AudioUnit SDK provided by Apple. Support for Cocoa UI is being added.

An extremely ambitious project, ARIAS is designed from the ground up to be the most comprehensive Long Term/Sub-Acute medical facility management and Electronic Charting (EC) system available and the ONLY solution available developed for Mac OS X Leopard